Dipper-stick end fitting



May 28, 1929.

.E. J. WILSON DIPPER STICK END FITTING Filed Oct. 15. 1927 attorney Patented May 28, 1929.

* Fr es.

EMERY J. WILSON, OF CLEVELAND HEIGHTS, OHIO, ASSIGNOR- TO THE TI-IEW SI-IOVEL COMPANY, OF LORAIN, OHIO, A CORPORATION OF OHIO. I I

DIPPER-STICK END FITTING.

Application filed October 15, 1927. Serial No. 226,387.

This invention relates to a novel form of end fitting or greenhorn on a dipper stick such as employed in connection between the boom and the dipper on a power shovel or the like; and the invention has particular application to the form or combination of boom and dipper stick disclosed in mycopending application Ser. No. 116,403.

The objects of the invention are .to provide a greenhorn for a dipper stick adapted for cooperation with the parts of such a boom including ordinarily a crowd pinion, whereby the maximum extension of the dipper stick will be increased, the maximum angular motion of the dipper stick in the boom will be increased, and disconnection of the dipper stick from the boom will be prevented. Running of the rack off the crowd pinion will involve no injury and return of the rack to engagement with the crowd pinion will be accomplished with facility.

The exact nature of the invention together with the further objects and advan tages thereof will appear from the following description taken in connection with the drawings, in which Fig. 1 is an elevation of a power shovel of the type to which reference has been made wherein a crowd pinion is employed, showing my invention applied thereto; Fig. 2 is a detail of a portion of the boom showing the end portion of the dipper stick and its mounting in the boom, all in normal operating relation; Fig. 3 is a view of the parts shown in- Fig. 2, showing the manner of functioning .of the end fitting; and Fig. 4 is a transverse section as in a plane passing through the axes of the parts 6 and 15*, Fig. 2.

The principal parts of the shovel are the cab 1 enclosing suitable drums, and means for operating the same rotatably mounted upon the carriage 2 and carrying a boom 3 which in turn carries the dipper 4: by means of the dipper stick 5 supported at its dipper end by suitable tackle; these parts in their general arrangement being well known in the art. According to the invention disclosed in my co-pending application to which reference has been made, the boom is built up of spaced structural members which form a longitudinal opening medially of it,'across it, through the members, passes a shipper shaft 6 carrying between the members'of the boom a crowd pinion 7, and upon an overhanging end, suitable means such as a sprocket, by which the pinion may be rotated. The side members of the boom are practically symmetrical about the shipper shaft both longitudinally and laterally. The dipper stick carries a rack 8 extending substantially throughout its length upon its shaft 6 on each side of the dipper stick and pinion is a generally circular surface'casting member 10, each of these castingsbeing suitably secured to the boom, the members 10 thus insuring" the proper alignment of the dipper stick between them by allowing free swing of the dipper stick in avertical plane.

Inwardly of each of the members 10 and concentric with the shipper shaft therethrough is a track 14;, and in this pair. of tracks is'arranged to run, in floating relation with the crowd pinion, a backing carriage for the dipper stick, the carriage comprising two roller assembly units circumferentially spaced by the links 15, each of the units including a pair of rollers 15 adapted to ride in the tracks 14 and a roller 15 therebetween and on the shaft thereof, adapted to bear upon the back of the dipper stick for maintaining the proper relationbetween the rack 8 and the pinion 7. The rack 8 is customarily made in sections independently secured to the dipper stick to form in effect a continuous rack along the length thereof, the dipper stick carrying also side plates 30 which provide metallic bearing surfaces against the members 10. According to my invention I provide for the end of the dipper stick a novel end fittingor greenhorn 31 preferably secured between the side plates 30. The lower surface of the inner or connecting end of the end fitting is provided with teeth in continuation of the teeth 8, the pitch line of the teeth, however, departing from the pitch line of the rack upwardly along a portion of a semi-circular "depression 32 on the lower surface of the ing upwards of the heel in a horn or toe 34:

dipper stick movable therein, and a crowd extending above the plane of the upper surface of the medial portion of the dipper stick and having a curved surface 35.

The functioning of the end fitting will be as follows: i

When the dipper stick is extended for wardly of the boom more than a normal amount, as from the position indicated in Fig. 2 to that indicated in Fig. 3, the rack 8 rides along the pinion 7 until the pinion is seated in the depression 32, which then closely surrounds the pinion as appears from Fig. 3, with the teeth on the pinion and depression respectively just clearing, so that continued rotation of the pinion (counterclockwise in the drawings) will not result in tooth breakage or movement of the dipper stick. In this position of the dipper stick the carriage 15 is engaged by the rollers thereof between the horn 35 and the upper surface of the dipper stick, thus preventing further forward movement of the dipper stick from the boom.

When the parts are in the position of Fig. 3, the tension of the line 36 supporting the dipper will tend to retract the dipper stick,

hence upon reverse rotation of the pinion 7- (clock-Wise in the drawings) the pinion will engage the immediate adjacent teeth in the depression 32 and rack the dipper stick back into its normal relationship with the pinion as appearing in Fig. 2.

From the above, it will be seen that although the ultimate extension of the dipper stick from its connection with the boom is made possible by the use of my invention, nevertheless, all possibilityof the end of the dipper stick running out is eliminated.

'lVhat I claim is:

1. In a power shovel having a boom, a

pinion foractuating said dipper stick, an end fitting on said dipper stick having oppositely extending heel and toe members adapted to engage said pinion and a mem ber carried by said boom respectively, to limit said dipper stick movement.

2. In a power shovel having a boom, a dipper stick movable therein and having rack teeth, a crowd pinion engageable With said rack teeth to effect dipper stick movement, and backing means for maintaining said dipper stick against said pinion, an end fitting on said dipper stick having oppo sitely extending toe and heel members adapted to engage said backing means and said pinion respectively, to limit said dipper stick movement.

8. In a power shovel having a boom, a

dipper stick movable therein and having rack teeth, and a crowd pinion engageable with said rack teeth to effect dipper stick movement, an end fitting having a depression, a portion of said depression having teeth in continuation of those of said rack,

and another portion being adapted to bear engage said boom members to limit said dipper stick movement.

5. In a power shovel-having av boom and a dipper stick movable therein between a rotary member of the boom and a floating backing structure, an end, fitting on said dipper stick having a depression fitting said rotary member anda horn adapted for engagement with said backing structure whereby dipper stick movement is limited.

In testimony whereof I hereby affix my signature.

EMERY J. wILsoN. 

